Needle-based medical device including needle guide and method for constructing

ABSTRACT

A needle-based medical device including a needle guide and a method for constructing the same are disclosed. The needle-based medical device includes a tube having a first lumen; a needle guide which is dimensioned to be inserted into the lumen of the tube, and a needle. The needle is inserted such that an end is positioned in the needle guide. A glue may also be provided to secure the needle guide to the tube. In one embodiment, the tube may be made of extruded plastic.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional patent application of U.S. patentapplication Ser. No. 11/536,236, filed on Sep. 28, 2006, currentlypending.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This patent application relates to medical devices that utilize a needlesecured to a hub, including but not limited to catheter assemblies,blood collection devices, huber needle assemblies, syringes, and otherneedle-based medical devices.

2. Related Art

Current medical devices that include needles are formed by the use ofmolded tubes, a needle, and a rigid hub to which the needle is secured.The needle hub may be made out of a thin extruded tube or a thin moldedtube. Devices of this type are shown in U.S. Provisional PatentApplication Nos. 60/659,213, 60/659,217, 60/659,226, and 60/714,954,which are incorporated by reference herein. This method of assemblingneedle-based medical devices presents several problems associated withthe use of molded tubes. One problem is the sheer expense of moldingeach individual tube used to form a device. The actual manufacture ofsuch devices is also problematic. Molding long, thin members for medicaldevices with molded tubes is difficult, particularly where the mold corepin must be supported at its distal end. Particularly in small gaugeneedles, the core pin must have an extremely small diameter, renderingit extremely fragile, difficult to support, and difficult to center.Additionally, each needle size requires a different size core pin toform the needle. In view of the foregoing, there exists a need in theart to overcome one or more of the deficiencies indicated herein.

SUMMARY OF THE INVENTION

A needle-based medical device including a needle guide and a method forconstructing the same are disclosed. The needle-based medical deviceincludes a tube having a first lumen; a needle guide which isdimensioned to be inserted into the lumen of the tube, and a needle. Theneedle is inserted such that an end is positioned in the needle guide. Aglue may also be provided to secure the needle guide to the tube. In oneembodiment, the tube may be made of extruded plastic.

According to a first aspect of the invention, a needle-based medicaldevice is provided, the medical device comprising: a tube having a firstlumen; a needle guide dimensioned to be inserted at least partially intothe first lumen, the needle guide including a second lumen and a gluewell; a needle having an end in the second lumen; and glue to secure theneedle guide to the tube.

According to a second aspect of the invention, a method of constructinga needle-based medical device is provided, the method comprising:providing a tube having a first lumen; providing a needle guide;inserting the needle guide into the first lumen; inserting a needle intothe needle guide; introducing glue into a glue well between the needleguide and the first lumen; and curing the glue.

According to a third aspect of the invention, a needle guide for aneedle-based medical device is provided, the needle guide comprising: abody for insertion into a first lumen of a tube, the body including asecond lumen to position an end of a needle.

According to a fourth aspect of the invention, a needle hub for aneedle-based medical device is provided, the needle hub comprising: atube having a first lumen; a needle guide having an outer surface forengaging the inner surface and a second lumen for positioning a needle;and a glue for hermetically sealing the needle, the tube, and the needleguide.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features of this invention will be more readilyunderstood from the following detailed description of the variousaspects of the invention taken in conjunction with the accompanyingdrawings, in which:

FIG. 1 depicts an isometric cross-sectional view of a medical device (acatheter introducer) embodying one embodiment of the invention.

FIG. 2 depicts an exploded view of a needle hub embodying one embodimentof the invention.

FIG. 3 depicts an isometric view of the needle guide showing a gluewell.

FIG. 4 depicts an isometric cross-sectional view showing the assembledneedle hub.

FIG. 5 depicts an isometric cross-sectional view showing an alternativeembodiment of the assembled needle hub.

FIG. 6 depicts an orthogonal cross-sectional view of the device shown inFIG. 1 showing one embodiment of accessing the glue well duringmanufacture.

FIG. 7 depicts an orthogonal cross-sectional view of the device shown inFIG. 1 showing another embodiment of accessing the glue well duringmanufacture.

It is noted that the drawings of the invention are not necessarily toscale. The drawings are merely schematic representations, not intendedto portray specific parameters of the invention. The drawings areintended to depict only typical embodiments of the invention, andtherefore should not be considered as limiting the scope of theinvention. In the drawings, like numbering represents like elements.

DETAILED DESCRIPTION

A device and a method are disclosed that provide an improved method ofproducing needle-based medical devices more effectively and efficiently.

Referring now to FIG. 1, one embodiment of a needle-based medical device10 is shown in the form of, for example, a catheter introducer 10 with aneedle shield 12, including components made from concentric extrudedtubes 12, 14, and 18. These concentric tubes include needle shield 12,outer housing 14, and needle hub 18. The use of extrusions substantiallyreduces the cost of such devices compared with existing devices made outof molded parts, although molded tubes may be used. Although medicaldevice 10 is described herein as a catheter introducer assembly, it isunderstood that the teachings of the invention are applicable to anytype of needle-based device, including but not limited to catheterintroducers, blood collection devices, huber needle assemblies, andsyringes.

Referring now to FIG. 2, tube 30, needle guide 20, and needle 16 areshown in an exploded view. Needle 16 has a distal end 26 and a proximalend 28, and is secured to needle guide 20. Needle guide 20 is secured totube 30, forming the needle and hub for a needle-based medical device 10(FIG. 1). Body 22 of needle guide 20 is inserted into distal end 38 oftube 30. Proximal end 28 of needle 16 is inserted into body 22 of needleguide 20. Tube 30 may be, for example, a plastic extrusion made ofpolypropylene, acrylic, or other similar material, and has a proximalend 36, a distal end 38, and a first lumen 32 extending between proximalend 36 and distal end 38.

Referring now to FIG. 3, a more detailed view of needle guide 20 isprovided. In one embodiment, needle guide 20 includes a body 22 forinsertion into first lumen 32 (FIG. 2) of tube 30 (FIG. 2). Body 22 mayinclude a second lumen 40 to position an end 28 (FIG. 2) of needle 16.In one embodiment, body 22 is generally cylindrical and further includesan outer surface 42. Body 22 is joined to distal end 38 by at least onerib 46 which extends from body 22. In one embodiment, the number of ribsmay be three, and each of three ribs 46 may be positioned approximately120 degrees from each other rib 46. It is understood, however, that anynumber of ribs greater than one may be used. As will be describedherein, empty spaces 48 lie between ribs 46, in a configuration whichforms a glue well 50 adjacent to the at least one rib 46 and first lumen32 (FIG. 2), and includes a space between proximal end 28 of needle 16and second lumen 40.

Referring now to FIG. 4, a first embodiment of an assembled needle hubis depicted, including tube 30 having first lumen 32, needle guide 20dimensioned to be inserted at least partially into first lumen 32.Needle 16 has proximal end 28 in second lumen 40, and a glue 56 ispositioned to secure needle guide 20 to tube 30. Proximal end 28 ofneedle 16 is inserted into second lumen 40 in needle guide 20, thesecond lumen having a diameter slightly larger than that of needle 16.In one embodiment, a friction fit is provided between second lumen 40and proximal end 28 of needle 16, maintaining substantiallycircumferential contact between the second lumen 40 and the needle 16.

Body 22 of needle guide 20 is inserted into first lumen 32 such that itis positioned coaxially with tube 30. Needle guide 20 may include aflange 44 coupled to at least one rib 46 at a distal end of needle guide20, which is positioned to engage with outer wall 34 of tube 30 whenbody 22 is inserted into first lumen 32. Flange 44 thus acts as amechanical stop, limiting the depth to which body 22 can be insertedinto first lumen 32. The ribs 46 have a diameter just smaller than thediameter of first lumen 32, which provides a mechanical fit between body22 and first lumen 32.

When body 22 is inserted into first lumen 32, first annular space 52 isformed between the inner wall of tube 30 and outer surface 42 of body22. This space ideally measures about 0.001-0.005 inch, which allowsglue 56 to flow via capillary action into first annular space 52 afterit is deposited in glue well 50. A very tight fit of ribs 46 is notpreferred because that may cause distortion of distal end 38 of tube 30.In one embodiment, a second annular space 54 is formed between secondlumen 40 and the outer surface of proximal end 28 of needle 16. In thisembodiment, annular space 54 is also filled with glue as part of gluewell 50 by capillary action; however, second annular space 54 is notessential to the practice of the claimed invention.

Referring now to FIG. 5, a second embodiment of the assembled needle hubis depicted. According to this embodiment, needle 16 can be pre-moldedinto needle guide 20 and then inserted into first lumen 32. The innersurface of tube 20 may include a depth stop to limit axial movement ofthe needle guide relative to the tube. The depth stop may be an abutment57 positioned on the inner surface of tube 30. Returning to FIG. 1, onceneedle hub 18 has been assembled, it can be used in a device such as thecatheter inserter or any similar needle-based device. Needle hub 18 mayalso be assembled during assembly of such devices.

A first embodiment of a method of constructing a needle-based medicaldevice is provided wherein the device is assembled as follows. Tube 30having first lumen 32 is provided along with needle guide 20. Needleguide 20, e.g., body 22 of needle guide 20, is inserted into first lumen32 until flange 44 abuts outer wall 34 of tube 30, preventing furtherinsertion. Proximal end 28 of needle 16 is then inserted into secondlumen 40 from distal end 24 of guide 20. Glue 56 is introduced into gluewell 50, and then flows by capillary action into first annular space 52between outer surface 42 of body 22 of guide 20 and inner wall of tube30. In an embodiment including second annular space 54, glue 56 is alsoallowed to flow into second annular space 54 between needle 16 and body22 of guide 20. Glue 56 is then cured.

A second embodiment of a method of constructing a needle-based medicaldevice is provided wherein the proximal end 28 of needle 16 is insertedinto second lumen 40 from distal end 24 of needle guide 20 before body22 is inserted into first lumen 32. In that case, the coefficient offriction between needle 16 and guide 20 must be greater than thecoefficient of friction between guide 20 and tube 30. In an alternativeembodiment, a press fit or serrations in needle guide 20 may be providedto hold needle guide 20 in place against the force of insertion ofneedle 16.

Referring now to FIG. 6, a first embodiment of accessing glue well 50during manufacture is provided. According to this embodiment, needleshield 12 may be threaded onto needle 16 from proximal end 28 (the bluntend) of needle 16. In that case, access to glue well 50 may be obtainedvia a cutout 62 in needle shield 12. Glue nozzle 64 is inserted intocutout 62 and introduces glue 56 into glue well 50.

Referring now to FIG. 7, a second embodiment for accessing glue well 50during manufacture is depicted. According to this embodiment, access toglue well 50 is provided while keeping distal end 58 of needle shield 12separate from needle shield body 60 (but still threaded on needle 16)during the gluing process. In that case, glue nozzle 64 is inserted intothe end of lumen 66 of needle shield body 60. Glue 56 is introduced intoglue well 50, after which, distal end 58 of needle shield 12 is snappedand bonded or otherwise attached to needle shield body 60.

The foregoing description of various aspects of the invention has beenpresented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formdisclosed, and obviously, many modifications and variations arepossible. Such modifications and variations that may be apparent to aperson skilled in the art are intended to be included within the scopeof the invention as defined by the accompanying claims.

1. A needle guide for a needle-based medical device, the needle guidecomprising: a body for insertion into a first lumen of a tube, the bodyincluding a second lumen to position an end of a needle.
 2. The needleguide of claim 1, further comprising at least one rib extending from thebody.
 3. The needle guide of claim 2, further comprising a flangecoupled to the at least one rib, the flange providing a depth stop byabutting an outer wall of the tube.
 4. The needle guide of claim 2,further comprising a glue well to receive glue to secure the body to thefirst lumen, wherein the glue well is positioned adjacent to the atleast one rib and the first lumen.
 5. The needle guide of claim 1,further comprising a glue well to receive glue to secure the body to thefirst lumen.
 6. The needle guide of claim 5, wherein the glue wellincludes at least one of: a first annular space between the needle guideand the first lumen, and a second annular space between the needle guideand the end of the needle.